Prepping 101: Pedal Powered Generator – K-TOR Power Box

The K-Tor Power Box
Pedal Powered Generator
http://www.k-tor.com/

The K-Tor power box is one of the few pedal generator options on the market today. It is strong enough to power small electronics, but little else.

The K-Tor power box is one of the few pedal generator options on the market today. It is strong enough to power small electronics, but little else.


One of the more memorable scenes from the 1973 film Soylent Green was Edward G. Robinson on his pedal powered generator, to keep the lights in a post collapse scenario. Is pedal power realistic? How much power do you get? We we able to try the $195 extremely innovative K-Tor Power Box, one of the few complete package options on the market. It generates 20 watts at a steady pedal rate. This is not a ton of power, but lets take a look at the actual numbers, plus a general review of the product itself. One of the nice features on the K-Tor is that it generates 120 volts, not 12v like most backup power systems. The power is DC, not AC, but you can plug your regular wall warts right into the K-Tor, because DC will pass through the power rectifiers in the wall wart. Most electronic devices run on DC, but electric motors are generally AC.
The pieces of the K-Tor Power Box.

The pieces of the K-Tor Power Box.


The watt as a measure of electricity is nice because it is proportional to volts. Watts equals volts times amps. This little generator isn’t going to give you enough power to cook or run a refrigerator. But where it will work is if you want to keep a radio or cell phone charged. These are very small consumption devices that run on a 3.8 volt battery using power voltage regulated from a 5 volt input, the voltage of a USB port. A normal phone or handled radio battery is 2600 mAh, or thousandths of an amp per hour. To figure how much consumption the phone draws in relation to the 20 watt output of the K-Tor, we can convert it to watt/hours. This is done by multiplying mAh times voltage, call it five volts, divided by 1,000. So it is 2,600×5/1000, or 13 watt hours. If you pedal the K-Tor for an hour, you’ll get 20 watt/hours. Then take the power consumption ratings for the phone, such as 17hrs. talk time, and you get some actual estimations of how much pedaling you’ll have to do to run simple devices. The circuit in a phone or radio usually only allows the battery to deplete 1/2 way to extend battery life, so factor that in as well. You should be able to recharge a standard phone battery in under an hour of pedaling.
The nicest feature of the K-Tor is that it supplies 120 volts, the same that your wall wart will be looking for to charge just about anything.  It sends DC current, not AC, but that is what most electronics are looking for.

The nicest feature of the K-Tor is that it supplies 120 volts, the same that your wall wart will be looking for to charge just about anything. It sends DC current, not AC, but that is what most electronics are looking for.


To run a 12 volt lightbulb (you can get 12v bulbs on Ebay and Amazon), usually you’ll be looking at 15 watts or so. So, just like the scene in Soylent Green, you could actually pedal and power a lightbulb. You will probably want to charge batteries instead though, and since the K-Tor supplies DC, you can do this directly.

The product itself has a good deal of plastic, and this is partly because it was really made for backpackers and campers who want to keep their phones charged. Plastic is light, but long term this product will most likely break. I would definitely plan to screw it down to a piece of wood, but you’ll also have to be careful not to twist the unit as you pedal. That would be bad.

This Samsung Galaxy S4 showed charging with slow pedaling.

This Samsung Galaxy S4 showed charging with slow pedaling.


Portable power generators, this one and a hand crank device, seems to be all that K-Tor does. They do, however, seem to be successful with the products, which is why we purchased it. Though horribly plastic, the K-Tor is not a bad product. If you can afford it, there are worse investments to keep in your prepping supplies, but it is pricey for a hunk of plastic with a small generator and a couple bicycle cranks. Please see the assembly and use videos below.
These are the power consumption numbers for a Samsung Galaxy S4.

These are the power consumption numbers for a Samsung Galaxy S4.


{ 20 comments… add one }
  • chris June 17, 2016, 10:14 am

    I have one. It charges a tablet with a bit of effort and you can charge several cell phones at once.
    I have had my tablet running and charging at the same time but it charges quicker if it is just off and charging.
    We made a pedestal for it from wood angled like in the video and it is much easier than having it flat on the floor.

  • West87 December 31, 2014, 1:43 pm

    I think a little diy could go a long way with this, as well as some gearing. We have made pedal generators at work using old modine heater motors and other fractional hp motors.

  • Guy smalley December 31, 2014, 10:32 am

    As a cat2 bike racer in my youth spending many hours in the saddle an hour doing that for a non cyclist is really unrealistic for the return on energy spent imo. Now i could see if it was a bottom brackett of a bike that was use part of a routine.

  • roy July 23, 2014, 12:34 am

    The kids can watch all the TV they want, which is to say, using all the power they can generate to run the TV.
    Perfect.

    • kenneth torino October 29, 2014, 10:59 pm

      Yes and video games. We have had many moms buy it so their kids can play video games when they go camping but they have to generate their own electricity. ken

  • Bob July 22, 2014, 3:21 pm

    Second attempt to add a comment: What am I missing here? Why would I want to lug this thing in the field just to light a 20 watt bulb?

    • kenneth torino October 29, 2014, 10:57 pm

      This will charge up most any portable electronics. Not just cell phones but ham radios and walkie talkies, Led lanterns, us water purifiers, gps etc etc etc. You can watch dvd’s in camp at time and the kids can play their video games. you name it. There are lots of things you can do with it. If you are hiking you are walking during the day and you will not want to stay put so your solar array can charge. you want to do it at night in your tent. Lost of good reason and applications for this. Thanks. Ken

  • dink winkerson July 22, 2014, 3:11 pm

    Kinda wondering, could there be an article in the near future, that might tell one how to hypothetically store firearms in the ground, for that shtf situation.

  • djw July 22, 2014, 12:30 pm

    Maybe hard wire this into my kids laptop or xbox!

    An opportunity in the making.

  • Tjtechster July 22, 2014, 11:08 am

    This article is extremely misleading, and can lead to damaging and probably destroying your wall wart!!
    Whomever wrote this article clearly has NO electronics experience!! A lot of wall warts have transformers in them to drop the 120VAC to a useable lower voltage.. If you put 120VDC though a transformer, it will immediately burn out the primary winding of the transformer, and destroy the wall wart…
    I’m not even sure any of the newer switched power supply wall warts will survive when plugged into 120VDC…

    • Administrator July 22, 2014, 12:25 pm

      they survive just fine. Transformers can’t handle DC lmao? The DC passes through the rectifier circuit just like AC does.

      • Larry July 23, 2014, 5:55 pm

        How is your phone going to work if the cell towers have no power?

    • kenneth torino October 29, 2014, 10:52 pm

      Most wall chargers are switching and they work fine and there is no risk. If you have something with an old transformer is will not harm it and it will not work. If you need it to work you just get a switching charger with the same output. Most devices stopped using transformers a long time ago. Still a few in the US who use them as they are not banned here. Europe lead the conversion to switching as they figured out they were wasting gigawatts. ken

  • qwester32 July 22, 2014, 9:42 am

    Back to school for you regarding volts, amps, dc watts, dc watt hours, etc. You got it sooooo wrong its almost uncorrectable. I suggest using the manufacturer’s data sheet and app notes. If it truly puts out dc amps at 120 volts it is lethally dangerous. There are solar power supplies for 1/3 the price at more useable safer outputs at Electronic Goldmine.com among dozens of others.

    • Russ July 22, 2014, 12:29 pm

      Thanks for the info. qwester32

    • kenneth torino October 29, 2014, 10:48 pm

      Quester, explain where you think the math is wrong. Volts time amps is watts, mAH is milli amp hours. It puts out 120 volts DC at 20 watts so the the amperage is very low and it is not dangerous at all. It is fully insulated. I am a fan of solar but solar works by accumulating charge with a big enough array in direct sunlight between 10am and 2pm. This is not always an option. This is the ultimate back up as it will always work. Ken

  • Mitchb July 22, 2014, 9:39 am

    Is this just another crock of green crap or what? Another joke which is what our country has turned into.

  • Mitchb July 22, 2014, 9:39 am

    Is this just another crock of green crap or what? Another joke which is what our country has turned into.

    • kenneth torino October 29, 2014, 10:41 pm

      Dear Mitch, this was designed and is manufactured in the US. The plastic is polycarbonate which is as strong as aluminum. This will keep critical electronics going anywhere anytime. You can pedal comfortably for long period of time so this is practical. Thanks Ken

  • Lying Bastard July 22, 2014, 3:01 am

    Now I can invite all my cyclist friends to my house to do their favourite activity: pedal away for hours. And, in the process recharge my batteries. Everyone wins!

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